An agency set up to investigate the issue, Higher Education Degree Datacheck(Hedd), said it had reports of more than 90 bogus institutions.

It follows a BBC South East investigation which found fake University of Kent degree certificates on sale online in China for £500.

Jayne Rowley, the higher education services director at Prospects which runs Hedd, said last September was its busiest month so far, with the closure of four bogus university sites and three websites selling fake degree certificates from multiple UK universities.

"One of the institutions we shut down in September was Stafford University. Now, of course there is an entirely genuine Staffordshire University, so they are piggy-backing on a name," she said.

"There are some sites where they've actually taken the name of a real university - Surrey for example.

"There was a bogus provider shut down by us a couple of months ago calling itself Surrey University, and we've had 'Wolverhamton university' without the 'p' in the middle."

Other fake certificates have purported to have come from Salford and Anglia Ruskin universities, while degrees from the University of Manchester were sold on the auction website eBay.